This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of the complete prior art. The best before date is a date that does not describe the time for a food product to be edible, but a date that the food product is expected to retain its qualities such as taste, color, crispiness, elasticity and mastication. When a food product has passed the best before date, the quality of the food gradually becomes worse, but the food may still be fully edible. Best before dates are applicable if the product has been stored properly. Often information on proper storage is included on the container. The expiration date applies to unopened packaging, but also an opened package can keep after the expiration date. Expiration date is used on food products deemed by the manufacturer to deteriorate rapidly and become a health hazard. That is the expiration date is the last day on which the manufacturer can guarantee that a food product can be consumed without any danger to health. Methods for labeling of expiration dates and best before dates is conventional black printing ink—often printed in small font for the consumer to discern these dates.
Packaged foods products often become waste because of uncertainty about if the food is spoiled or not. There are no quantitative means to determine if packaged food is spoiled in the food chain. One of the great problems of mankind is to feed a growing population on with a limited supply on earth. In the twentieth century's later half, enormous progress in agricultural productivity was made, particularly in the third world. Today the development has stagnated and attention is directed towards the losses in later stages of the food chain. In the developed world, it is estimated that as much as 30% of the food go to waste, either because we can not manage to eat it, or because it is unfit to eat or sell. The global food wastage contribute to double of the carbon emissions of global air traffic.
In the following known means for alleviating the above problems will be described:
A time-temperature indicator that that is configured as a bar code is described by EP1901925B1 (Tempix AB).
3M's MonitorMark is an indicator with the that uses diffusion to provide a time-temperature indicator.
VITSAB's time temperature indicator is based on a color shift from enzymatic hydrolysis of a lipid substrate.
Lifelines Inc.'s color indicator FreshCheck is based on a polymerization reaction that leads to a colored polymer.
TimeStrip's indicator shows a coloring effect for a time lapse from pressing a button.
Insignia Technologies' indicator shows a coloring effect over a large color interval of brown, orange, violet upon exposure to UV-light and opening of a package.
FreshController—is a visual indicator that shows the freshness of a package after a package has been opened. This by a time lapse effect by a diffusion mechanism.
Even if all these technologies have been successful in their respective fields, they are too expensive compared to the benefits and would increase the cost for the products that they are applied to. Therefore, there's limitations of using these indicators or sensors for a large food product segment at low cost for food products with low margins and general food products. Furthermore, the indicators competes with the best before dates.
A freshness indicator is disclosed in WO03087955, in which the indicator provides easy determination if a food product is still suitable for safe consumption after a certain time has elapsed from the date the package is first opened and/or unpacked. The indicator comprises a programmable controller with a separate power source in combination with at least one display means and/or at least one audio element. There is at least one sensor and the timer for the indicator. The document also discloses that the sensor is triggered by an external means. The invention can be used for a package.
The patent application FR2809519A discloses a method and apparatus for controlling the freshness of the products that are perishable after opening a package. The device consists of a housing with an optical reader of bar codes, a memory, an internal clock, a counter, a display and keys. The device can identify the product, with respect to storage conditions calculate and suggest to the consumer a new expiration date earlier with regard to the opening of the package.
In the application WO2001082006A1 a technology for a consumable expiration date indicator is disclosed characterized in that it comprises a thermal paper or an iridescent temperature sensitive material which is controlled by a circuit or integrated circuit for indicating a predetermined expiry date visually and automatically. The invention essentially comprises a thin patch that may be secured or attached to the packaging of an area which clearly changes color. The document also describes that an LED can be used to change brightness when the predetermined expiry date is reached.
The application WO2006032834A1 describes a timer unit to monitor the time period associated with foods and other substances with a finite time as these are suitable for use. The timer unit is programmable by a user to monitor a plurality of time periods, where each time period is identified by a unique code as an alphanumeric code. The tags can be attached to a product such as a lid to a food jar, and its identifiable code can be entered on a keypad on the timer unit so that the period during which the tag is attached can be controlled and can be read at any time during the default period during which product in the can is edible. The device helps to ensure the safe use of food products and reduces product waste.
Furthermore, the patent application U.S. Pat. No. 5,802,015A describes an electronic timer label to indicate the end of a period associated with a specific article. The label comprises a pulse generator and a binary counter. The pulse generator is configured to generate a series of pulses at a predetermined pulse, and the counter is configured to count from an initial count in response to the series of pulses and for generating an output signal on attainment of a final count. The label also includes a display that indicates the end of the time period, a programming port to control the programming pulses to the counter, and a mechanism to affix the label to a surface of a product.
The patent application WO2007/064541 describes an electronically printed chromatic elapsed time indicator device comprising a switch, a power source and a voltage-driven elapsed time display means for displaying the elapsed time in the activation of a switch and regardless of the actual date of activation thereof. The components are functionally connected to each other and are printed on at least one substrate.
The patent application US2004/156418A1 describes an electronic time-temperature indicator that may appear in a label indicating that the time or temperature levels have been reached which may jeopardize the quality, durability, or safety of the item label is arranged on. The label can be used on a variety of items that require careful handling when it comes to temperature and/or time elapsed before use. The label may be in the form of a flexible, disposable label that usually is powered by a small battery.
The patent application GB2344101A discloses a timer device which comprises an electrochemical structure which provides a visual indication of elapsed time.
The patent application GB2443486, discloses an attachable, reusable electronic device that counts the days of storage of perishable goods. The device measures a time from when a fresh product is exposed to air upon opening or breaking a package. It may also include a flashing warning light to indicate when one day remains. The unit can be connected to the goods themselves. The unit is programmed by the user or have a preset time. The patent EP2390203B1 describes a package that has a wall with a sensor on the inside of the package and an antenna on the outside of the package to communicate information about the contents of the package with the antenna on the outside of the package. The package wall is an electrically conductive layer extending between the inner side and the outer side to communicate information about the contents of the transponder on the outside of the package to an external transponder reader. The problem with the technology is that the electrical connection between the inside and the outside of the packaging is very difficult to achieve in practice for most food packages.
It would be very useful for the art if an alternative to conventional expiration dates and best before dates of packaging could be provided to reduce food wastage. To meet the need of a packaging indicator for increased food safety and reduced food wastage, it would be desirable to provide a food status indicator with relatively inexpensive components. The color change of the indicator would also need to be reliable in order to replace conventional best before dates, otherwise there is a risk that the consumer gets confused by mixed messages.
The present invention eliminate, prevent or overcome the aforementioned problems of the prior art, which would be a step towards the application of food status sensors in the food supply chain having the features in the appended claims. The present technology solves the problems of the conventional best before date, whose drawbacks have led to the art of color indicators. Furthermore, the present technology seek to solve problems of using an electrical connection from a sensor on the inside of a package to the outside to detect the status of the food inside of the package.